Method of building up air tubes for pneumatic tires



SeptA 1,' y19.25. 1,551,999

T. B. MCLEROTH METHOD OF' BUILDING UP AIR TUBES FOR` PNEUMATIC TIRES Filed May 1, 1924 2 Sheets-Sheet 1- T.B.MCLEROTH v 2 ShetlfShaet 2 iled May l, 1924 fr0/PNE rs Sept. l, 1925.l

METHOD onufILDING UP AIR TUBES Fon PNEUMATIC TIRES Patented Sept. 1, 1925.

UNITED STATES 'GEA 'THOMAS BAKER 'MCLEROTH OF LONDON, ENGLAND, v.AssferNonTo Tfn. `1`vreLE1toT1-1 (TUBES) LIMITEQOFLONDON, ENGLANDQABRTTISH COMPANY. A

METHOD or BUILDING ne Arkansas FONTNEUMATIG TIRES.

.Application ieany 41,

'To all whom it may concer/n:- f

Be it known that I, THOMAS BAirEaMo- LEROTH, of 6 Lincolnslnn' Fields, London, WV, SC; 2," England, railway engineer, have invented certain new and useful Improvements in Methods of Building Up Air Tubes forlpneumatic Tires, of which the following is'a specication. Y Inthe specifica-tion ofvmy application for 10 Letters Patent Serial No` 623,393, filed 7th March, 1923, isl-described and claimed a method of producing a multicellular lair tube into each of the cells offwhich projects a valveless feed tube communicating with a common feed or inflating passage constituted bya tubular strip or patch running around the inner periphery of thetube.' According to said method the tube proper and the tubu` ber'feed'tubes to the raw rubber from which the tube proper. is built up, instead of to a tubular V strip or patch, and in applying to theraw rubber from which the tube proper isbuilt up a strip orstrips o f raw rubber -to build up the common feed passage.`

A further modification consists in building up the tube proper from a strip of raw rubber by uniting the lateral margins of said strip so that the valveless feed tubes project outwardly, (i. e. building up the tube inside out), inserting intoone end of such tube a ring, introverting said lend of the tube, solutioning or otherwise securing to said tube, where it bends over said ring, a vdisc of raw rubber, further introverting said tube and securing another disc of raw rubber, and so on in succession;

Preferably the additional strip or strips of raw rubber, for the formation of the common feed passage, is or are applied be'- fore such introversion and the.endsofthe length of tube are joined up to form an annulus after such introversion, after which Y an additional layer or layers of raw rubber may be arildltowhe meer periphry of ,the tube Yand :the latter'may then be vul-v lcanizedg' ,i' .1

- The accompanyiiigA drawings serve tot il lustratehowl they method, in accordance with lone form of this invention, Vmay be carried out. 'In thefaccompanying drawings Figure ly is a fraginentary` perspective viewl of the strip of araw rubberffrom 'which' the tube proper islbuilt up," shew ing the'feed tubes.

o fjparti'ally vulcanized rubber Qin .position c "thereonV and also" strips of-frawrubber for forming the common feed passage; Figure Y 21s a'cross setion ofthe tube afterthe edges ofthefstripsjhavejbeen joined andbefore the tube is "introverted-g Figure I 3 Vis `'a `sec-` tional' elev'ation illustrating thev introversion y of the tube; Figure 4f is a cross-'section ori the line' 4 4, Figure w3 and `vFigurl'e 5 vis Y a cross.-v section of 'thef` tube afterl introversion and afterfformation 'of the 4common feed'passage.

-j-"A'st'rip `of raw rubber a, ofnotlles's than 'i the circumferential length of the't'ube tobe i produced ahd'of a lwidth corresponding with the cross section fof said tube, has mounted alongla line `lnear-ione lateralA margin a series of partially vulcanized feed i tubes 'b ,with so-oalled studs 0 Lf.; (such," for in'stance,'as described "and claimed in' thev specification of my prior fLe'tters Patent' No.` 1,470,239 the n eclrs d of'said'f studs passing through Vnot only thefraw vrubber "afand the fabric washers@ as in saidprior invention but also threu'gli'a'i's tr.i`'p'j;c ofl 'stock inet v running along t'hestri'pV offraw' rubber a andV of a lwidth correspondingwith thatofth'e common feed passage to be produced. A strip of raw rubber g with a similar strip of stoclrinet fabric z secured along its length is then secured to the strip a on the side remote from the feed tubes Z) along a line parallelwith the row of feed tubes and nearer the centre of width of the strip a. The edges of the strip o are bevelled and said strip lis ysecured to the ystrip a. by solutioning one of saidy edges and pressing it on to the strip a ,by means rubber 1' like, but slightly wider than, thel strip g and without any stockinet fabric thereon. The edges ofthe strip'aj are` then'4 sof scafed and lap jointed, as atn (orthey may be butt jointed), ysaid strip being so folded round in making the tube that the Valveless.

' rubber feed tubes .'A. .project outwardly the itu-ee so meer, thefts te say the tube is made inside out, as shown in Fig*- ure 2. l y n n A steel rin'g Zh; is slipped i'nt'o one end of thistube, (afterthe strips gaand y'A bay-,e been folded back as shown in Figure 4), and saidV 'end is then -ntreferted. e, dlsteneefeerrey ,Sreldne with the nite-131 eftheireed tubes Z9 as shown in Figure 3. Theffold of tbe-tube Where' ,it bends. over seid; ring le .iethen suitably eleened'wth nsphthe-or like eevent and. a raw rubber? dise ne, the edges of which; here%`e.eer.1.y seated' solutonedis pree'sedeeenst the; reeurvedi end ,of Vthe tube bismeans-io-ff a roller. The -tube is then further -i-ntroyerfted, the dise m Vpassing through the steel ring-Jp, andthe process lof Cleaning the. tube `andi wp-plyng another disc wz is repeate'dfsolid ammonia or like l Y30g.

Y substance, and if desired, French lchalk also, being? introduced iii-toolthe c'elll ofy the air said .joint is enolosejdby the coinrnon VfeedV passage, and then f-fold-ing over the strip jfand -so-lu-ti-oni-'ng end, Vpressi-ng its free -edge tothe 'st-rip v a and Vprefera'b'ly valso so-ln-tioning,- Iits inner"fateto Ttheiouter :face of the stripe. `.A su-itablexafpertur is cut in the outer Wall g', it, j. of the Common iniating passage, a valvef-(uotsbewn),fis -rnounted in position by means tof Ythe usual .patchend 'r theftube is then 'slightly` inflated, placed in an annular 'mould (such, for instance, as 'desc-rilxed and illustratedY in the specification and drawings accompanying my application Y for] Letters Patent'Serial No. 623,392 filed 7th March 1923) and further iinflated, .thus

causing theV ra'W rubber at Land;towards the` outer periphery Vof the mould to stretch and take up the shape of the mould.y The'vul- VCariization is 'then oarried out in the usual mennen Y If desired7 instead of forming the coinrnon feed passage from the strips g, L, j, as above set forth, *a Vsinglejstrip of raw lrubber may be applied by its edges to theV tube. Suche) stri-p Ina-y: be secured Yalongits one'edge'beforethe'strip-ey has been formed into artube, i

or 'along both its edges veither before or' after introversion' 0f said tubernon feed passage is so formed Yan additional thickness for thicknesses of raw rubber Inay `be'so-l-utfioned orotherwise 'caused'to adhere to the inner periphery ofthe tube, such additional; rubber Apreferably, being stretched a-S. i@ xiS 'applied f'so Vvajsto .tend to contract the nneriperphery 'ofthe JBube. f Y e.

l fclam.; i i e y The improved method of build-ing nir' tube 'forwa pneumatic tire of the kind herein'before' set forth, Which consists in securing V-alveless partiallyv-yuloanized rubbervfeed tubes to kafst'ripl of raw rubber, forniingsfidfstrip into atube by unitingthe iateralpinargins of said EVstrip so 4that the yalveless feed tubes project'outWar-dly, in-f Y sertinga ring into :one end of, such tube, in'-v troverting said'endfof 'the tube, securing to said tube, Whereit bends over said ring, ja disc of raw rubber, further introvertingsaid tubefand securing lanother disc -ofraw rubber, fand soqfon in succession, said ldiscs dividing said tube into a series of A'compa'rtrnents When the oolnand being "securedv thereto interrnecliately oi the -yalveless Yfeed tubes, KVVcutt'ingsoff a prede vte'frrn-i-nied length of said tube,uniting its ends to form an annulus 4and VVulcanizing said tube, `substan'tial-ly'as-set forth. Y

THQMAS BAKER MQLEROTH. 

